This herb is considered toxic.
(while some Chinese herbs are toxic, it must be noted that many come prepared, or are combined, to mitigate their toxicity)

Chinese Herb Dosage

4.5-9 grams in decoction 12

4.5-9 grams in decoction 13

Chinese Herb Notes

Guang Fang Ji contains aristolochic acid, a known nephrotoxic compound. The traditional method of preparation (boiling in water) is believed to lower the toxicity since aristolochic acid has a low water solubility but extreme care should be taken.

In Belgium, a weight loss clinic used a large dose of the raw powder along with acetazolamide and several other compounds resulting in at least 53 cases of renal fibrosis.